平行线路纵联零序方向保护安全性分析

着眼于纵联零序方向保护的安全性,探讨了平行线路区内区外各种接地故障,研究发现,对于两侧均无电气联系的平行线路,纵联零序方向保护一定误动;对于一侧或者两侧有电气联系的线路(包括部分平行),是否误动取决于两者间联系是磁强于电还是电强于磁;对于一侧共母线的系统,此时纵联零序方向保护其实是安全的;对于同杆并架线路,纵联零序方向保护的安全性亦能得到保证。

Safety Analysis on Pilot Zero Sequence Direction Relay Applied in Parallel Lines

Based on the safety of pilot zero sequence direction protection, the ground faults in parallel lines are discussed. It is concluded that the pilot zero sequence direction relay mal-operate certainly in parallel lines without electricity contact on both sides. For systems (include ones with part parallel lines) with electricity contact on one side or two sides, whether the relay will mal-operate or not depends on the relationship of which one is stronger between electricity and magnetic. For systems with one side or two sides on the same bus, the relay is safe in nature.